description:
  remove empty directories
synopses:
  - rmdir [OPTION]... DIRECTORY...
options:
  --ignore-fail-on-non-empty: ignore each failure that is solely because a directory is non-empty
  -p, --parents: remove DIRECTORY and its ancestors
  -v, --verbose: output a diagnostic for every directory processed
  --help: display this help and exit
  --version: output version information and exit